How accurate is the pelvic and transvaginal ultrasound for early detection of ovarian cancer? I saw a special on the TV and the doctor said even with a transvaginal ultrasound it is hard to see cancer untill it is in it late stages. If they can see a very small microscopic cyst on my ovarian that is not cancer how can they not see ovarian cancer tumor?

Not very accurate at all, unfortunately. They cannot see a microscopic cyst on your ovary. They can see small things, but not microscopic things. For example, a human egg cell (the largest cell in the body) is just barely visible to the naked eye. Ultrasounds cannot detect those, they're too small. They can detect the follicles, which eggs are inside of. The follicles are bigger than the egg cell itself. In any case, one of the problems with ovarian cancer is that it can sort of erupt everywhere at once. Tumors release BILLIONS of cells into your body. Most ovarian cancers start out in the outside casing of the ovaries, and that cell type is the same as the type that lines your abdominal cavity and organs. That means the cancer cells have an affinity to grow in those other places so once the still-pretty-small ovarian cancer starts releasing cancerous cells into the body, they very quickly latch on and start growing all over your abdominal wall, uterus, etc., usually, meaning ovarian cancer almost starts out as metastatic, and each of these metastases is microscopic, indistinguishable from any other part it's next to. In other words, the early stage (stage I) might be so quick that it's highly unlikely that anyone would be looking during that time period for the cancer, and even if they looked, it's easy to overlook or it might still be too small to see with any tool we have--the ovaries produce lots of stuff and change throughout the month, which is why it's really really difficult to find a cancer early in a woman during childbearing years, and it's only when a woman is outside of those years that they can easily see ovarian changes. There might be a window of only a month or two when it's big enough to be detectable by the most adept ultra sound technician, yet still hasn't spread very far, or it might spread before it's detectable. Of course, it could take longer than that for the cancer to spread. It's just that in many cases, that's the scenario. Even if it takes a year, two years, or three years, the tumors are all still small enough that the doc can't detect them via a regular exam, and they may not be causing any symptoms because they're each small even though their total mass may be substantial. But no one gets an ultrasound that often anyway. FYI: I had ovarian cancer, got treated, got healthy. Then got ultrasounds every three months for eleven years to see if it had come back. I got a clean bill of health at most of them, though a couple times it looked like I might have tumor growth, and I had an MRI, and it was nothing. Just false alarms. False alarms are frequent with ovarian cancer given the nature of the ovaries to produce cysts all the time. Then, two months after a checkup, after ELEVEN YEARS, I felt something was wrong, and sure enough, there was a tumor there, fully visible. We could compare it to the ultrasounds of 2 months earlier. It looked totally normal and healthy two months before a visible tumor was present. This was in someone checking ALL THE TIME and at high risk. No one else checks that often. That's the grim truth.